Imagine you're shooting in a studio. But instead of sitting behind the camera, you're on a sofa a few meters away directing the subject. You look at your iPhone to check the exposure setting; it's correct and you press the virtual shutter button on the handset and the camera snaps the photo.

This scenario is not a dream. XEqual has developed a Bluetooth receiver unit and app that work with Bluetooth-enabled iPhone and iPod Touch units. The receiver unit plugs into the GPS port on most Nikon cameras including the latest D7000 and D3100. Users can then control the camera's settings via the iOS device. bluSLR is also capable of recording your geographical data to geotag the photos.

The blueSLR receiver costs $149, and the accompanying app can be downloaded via Apple's App Store for free.